A new success for Leonard makes Sheldon very jealous and throws Penny for a loop. Meanwhile, Koothrappali pushes Lucy too far in their relationship, on the sixth season finale of The Big Bang Theory airing Thursday at 8/7c. On CBS.

The CBS comedy “The Big Bang Theory” is one of the highest-rated shows on TV. Jim Parsons, who plays the lovable genius Sheldon Cooper, talks to the “CBS This Morning” co-hosts about the show has changed his life.